The present invention generally relates to an analog to digital converter, and more particularly to an analog to digital converter affording high precision at low cost.
High precision analog to digital converters find wide application in diverse fields such as telecommunications, industrial process control, robotics, medical and scientific instrumentation, and digital disc audio systems to name just a few. Even though prior art high precision analog to digital converters are costly, their use in the above mentioned fields is justified because of the overall costs of the systems in which they are employed, because there are few alternatives to their use, or because they still represent an overall price reduction to the ultimate user when compared to other alternatives.
One application, however, awaits a low cost high precision analog to digital converter. That application is in the field of home audio digital cassette tape recorders. Such systems have not utilized digital formats because the cost of the required high precision analog to digital converters has not allowed these systems to compete with the commercially accepted analog audio cassette tape recorder systems. This is indeed unfortunate because, as well known, digital audio provides recordings having broadened frequency response, wider dynamic range, and reduced noise. The present invention however, provides a high precision, low cost, analog to digital converter which can allow audio digital cassette tape recorders to compete with their analog counterparts.